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1.
J Exp Bot ; 2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39177779

ABSTRACT

Despite the existence of over half million species of plant-eating insects, our planet remains predominantly green. In fact, susceptibility to herbivory is the exception, as plants are resistant to most insect species. This phenomenon is known as nonhost resistance (NHR), where every individual of a plant species is resistant to all variants of a pest or pathogen. While NHR represents the most common and durable outcome of the plant immune system, several aspects of this type of plant defence remains elusive, particularly in plant-insect interactions. In this review, we clarify the concepts of NHR in plant-insect interaction. We emphasize that NHR is a phenomenon arising as a consequence of effective plant defences providing invulnerability to most insect herbivores. This underscores that NHR is one of the main ecological features delimiting the range of plant-insect interactions on Earth. We further highlight the traits and molecular components of the plant immune system known to participate in NHR against insects. Finally, we discuss how NHR can be leveraged as a tool to develop pest resilient crops. Given the significant threat insects pose to global food security, research in plant NHR represents a crucial focal point with immense potential for ensuring food security worldwide.

2.
Porto Biomed J ; 9(3): 254, 2024.
Article in English | MEDLINE | ID: mdl-38835655

ABSTRACT

Background: This literature review explores the role of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and neutrophil-lymphocyte-to-platelet ratio (NLPR) biomarkers, as potential indicators for predicting bacteremia and sepsis in patients with cancer. Objective: Tracing the evolution of interest in this area since 2001, the aim of this review was to report a comprehensive overview of current knowledge and gaps, particularly in patients undergoing immunosuppression. Summary of Findings: The literature research indicates the potential of NLR, PLR, and other biomarkers in diagnosing and predicting sepsis, with some studies emphasizing their value in mortality prediction. A specific focus on bacteremia shows the effectiveness of NLR and PLR as early indicators and prognostic tools, though mostly in noncancer patient populations. While NLR and PLR are promising in general cancer patient populations, the review addresses the challenges in applying these biomarkers to patients with neutropenic and lymphopenic cancer. The NLPR could be considered a significant biomarker for inflammation and mortality risk in various medical conditions, yet its diagnostic accuracy in patients with immunosuppressed cancer is not extensively validated. Conclusion: This review offers a snapshot of the current research on biomarkers in patients with immunocompromised cancer in the sepsis and bacteremia area. More focused research on their application is necessary. This gap underscores an opportunity for future studies to enhance diagnostic and prognostic capabilities in this high-risk group.

3.
Indian J Hematol Blood Transfus ; 38(3): 492-498, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35747568

ABSTRACT

Gastric mucosa-associated lymphoid tissue non-Hodgkin lymphoma (gMALT NHL) is the second most common gastrointestinal lymphoma (50% of all gastric lymphomas), being closely associated with Helicobacter pylori infection, justifying that antibiotic therapy is effective in over 75% of all cases. This is a retrospective study analyzing all adult gMALT NHL cases diagnosed and treated in a single center for 8 years, focusing on demographic features, treatment outcomes, and survival analysis. Sixty patients with a median age of 61 years (53.3% female gender) were analyzed. Most of the cases had localized disease (66.7% were Lugano stage I) and had low IPI scores (median: 1). There was a high prevalence of Helicobacter pylori infection (68.3%). Nearly 97% of the cases received treatment for the disease, a median of one line; 55% of the patients treated endured complete response after first-line therapy (mostly antibiotics). Median overall survival time and median progression-free survival time were not reached. The mean follow-up time was 81.8 months (95% CI: [73.3-90.3]). Thirty-six patients (60%) achieved a 3-year follow-up time; the mortality rate was 15% at the end of the study. Age superior to 65 years and transformation into DLBCL were statistically significant negative prognostic markers for survival in this study (p = 0.006 and p = 0.033, respectively). Our study confirms that gMALT NHL is an indolent disease with long-term survival. Many patients, however, are exposed to several treatment lines along their disease course.

4.
Indian J Hematol Blood Transfus ; 37(3): 492-496, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33424149

ABSTRACT

Gastric diffuse large B cell lymphoma (DLBCL) represents the majority of all gastric lymphomas. We report a series of gastric DLBCL diagnosed and treated in a single center, between 2010 and 2018 (included). We retrospectively analyzed the population demographic features, treatment outcomes and survival. One-hundred-and-one patients were studied, 50.5% males and median age of 64 years [23-94]. Lugano staging was I in 16.8%, II1 in 20.8%, II2 in 10.9%, IIE in 13.9% and IV in 34.7% of cases. Twenty percent had Helicobacter pylori infection. R-CHOP-like therapy was used as first line in 96.9% of the patients. A complete response was achieved in 80% after first line therapy. At 3-years of follow-up (FU), 54% were in complete remission. The mean FU time was 73.6 months. Median overall survival and median progression free survival were not reached. We identified seven factors with negative impact in survival: age above 65 years-old (p < 0.01), ECOG 2-3 (p < 0.01), B symptoms (p = 0.001), bulky disease (p = 0.003), IPI 3-4 (p = 0.001), more than 3 treatment lines (p < 0.01), absence of response to first line treatment (p < 0.01). This study demonstrates that gastric DLBCL is a potentially curable disease with R-CHOP-like therapy, entailing long term survival and comparing well with other published series.

5.
Sci Adv ; 5(12): eaay0370, 2019 12.
Article in English | MEDLINE | ID: mdl-31840071

ABSTRACT

Dissecting the molecular landscape of fibrotic disease, a major unmet need, will inform the development of novel treatment strategies to target disease progression and identify desperately needed therapeutic targets. Here, we provide a detailed single-cell analysis of the immune landscape in Dupuytren's disease, a localized fibrotic condition of the hand, and identify a pathogenic signaling circuit between stromal and immune cells. We demonstrate M2 macrophages and mast cells as key cellular sources of tumor necrosis factor (TNF) that promotes myofibroblast development. TNF acts via the inducible TNFR2 receptor and stimulates interleukin-33 (IL-33) secretion by myofibroblasts. In turn, stromal cell IL-33 acts as a potent stimulus for TNF production from immune cells. Targeting this reciprocal signaling pathway represents a novel therapeutic strategy to inhibit the low-grade inflammation in fibrosis and the mechanism that drives chronicity.


Subject(s)
Dupuytren Contracture/genetics , Fibrosis/genetics , Interleukin-33/genetics , Receptors, Tumor Necrosis Factor, Type II/genetics , Tumor Necrosis Factor-alpha/genetics , Cell Line , Dupuytren Contracture/drug therapy , Dupuytren Contracture/immunology , Dupuytren Contracture/pathology , Fibrosis/drug therapy , Fibrosis/immunology , Fibrosis/pathology , Humans , Inflammation/genetics , Inflammation/immunology , Inflammation/pathology , Macrophages/immunology , Macrophages/pathology , Molecular Targeted Therapy , Myofibroblasts/metabolism , Myofibroblasts/pathology , Signal Transduction/genetics , Single-Cell Analysis/methods , Tumor Necrosis Factor-alpha/immunology
6.
BMC Cancer ; 18(1): 1245, 2018 Dec 12.
Article in English | MEDLINE | ID: mdl-30541488

ABSTRACT

BACKGROUND: Most patients with chronic myeloid leukemia (CML) treated with tyrosine kinase inhibitors (TKIs) will relapse if treatment is withdrawn, but various trials have recently demonstrated that a significant proportion of patients who achieved a stable and deep molecular response (DMR) can stop therapy without relapsing. However, most information on treatment cessation was obtained from clinical trials with strict recruiting criteria. METHODS: We evaluated the outcome of 25 patients with CML that discontinued TKI therapy in our institute in real-world clinical practice. RESULTS: Of the 25 patients, 76% discontinued therapy in sustained deep molecular response (SDMR) and 24% were in unsustained DMR (UDMR). Discontinuation of therapy due to adverse effects was observed in 5 and 50% of the patients in the SDMR and UDMR groups, respectively. After TKI discontinuation, patients were followed for a median of 24 months. At the time of this analysis, 56% patients had a molecular relapse after a median of 4 months. SDMR and longer treatment duration were associated with lower probability of molecular relapse: 25% in SDMR patients with TKI treatment > 96 months and 85% in UDMR patients with TKI treatment ≤96 months. All relapsed patients promptly resumed TKI therapy and regained at least major molecular response (MMR). CONCLUSIONS: Our results suggest that TKI discontinuation is safe outside clinical trials and particularly effective in CML patients who are in SDMR with longer TKI treatment duration.


Subject(s)
Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Protein Kinase Inhibitors/administration & dosage , Withholding Treatment/trends , Adolescent , Adult , Aged , Cytogenetic Analysis/trends , Female , Follow-Up Studies , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Male , Middle Aged , Recurrence , Retrospective Studies , Treatment Outcome , Young Adult
7.
Proc Natl Acad Sci U S A ; 115(19): E4463-E4472, 2018 05 08.
Article in English | MEDLINE | ID: mdl-29674451

ABSTRACT

A major discovery of recent decades has been the existence of stem cells and their potential to repair many, if not most, tissues. With the aging population, many attempts have been made to use exogenous stem cells to promote tissue repair, so far with limited success. An alternative approach, which may be more effective and far less costly, is to promote tissue regeneration by targeting endogenous stem cells. However, ways of enhancing endogenous stem cell function remain poorly defined. Injury leads to the release of danger signals which are known to modulate the immune response, but their role in stem cell-mediated repair in vivo remains to be clarified. Here we show that high mobility group box 1 (HMGB1) is released following fracture in both humans and mice, forms a heterocomplex with CXCL12, and acts via CXCR4 to accelerate skeletal, hematopoietic, and muscle regeneration in vivo. Pretreatment with HMGB1 2 wk before injury also accelerated tissue regeneration, indicating an acquired proregenerative signature. HMGB1 led to sustained increase in cell cycling in vivo, and using Hmgb1-/- mice we identified the underlying mechanism as the transition of multiple quiescent stem cells from G0 to GAlert HMGB1 also transitions human stem and progenitor cells to GAlert Therefore, exogenous HMGB1 may benefit patients in many clinical scenarios, including trauma, chemotherapy, and elective surgery.


Subject(s)
Cell Cycle , Fractures, Bone/therapy , HMGB1 Protein/physiology , Hematopoietic Stem Cells/cytology , Muscle, Skeletal/cytology , Regeneration , Animals , Cells, Cultured , Chemokine CXCL12/metabolism , Hematopoietic Stem Cells/physiology , Humans , Mice , Mice, Knockout , Muscle, Skeletal/physiology , Osteogenesis , Receptors, CXCR4/metabolism , Signal Transduction , Wound Healing
8.
Biochem Biophys Res Commun ; 499(2): 260-266, 2018 05 05.
Article in English | MEDLINE | ID: mdl-29567473

ABSTRACT

Tumour necrosis factor (TNF) is produced by primary human macrophages in response to stimulation by exogenous pathogen-associated molecular patterns (PAMPs) and endogenous damage-associated molecular patterns (DAMPs) via Toll-like receptor (TLR) signalling. However, uncontrolled TNF production can be deleterious and hence it is tightly controlled at multiple stages. We have previously shown that Bruton's tyrosine kinase (Btk) regulates TLR4-induced TNF production via p38 MAP Kinase by stabilising TNF messenger RNA. Using both gene over-expression and siRNA-mediated knockdown we have examined the role of Btk in TLR7/8 mediated TNF production. Our data shows that Btk acts in the TLR7/8 pathway and mediates Ser-536 phosphorylation of p65 RelA and subsequent nuclear entry in primary human macrophages. These data show an important role for Btk in TLR7/8 mediated TNF production and reveal distinct differences for Btk in TLR4 versus TLR7/8 signalling.


Subject(s)
NF-kappa B/metabolism , Protein-Tyrosine Kinases/metabolism , Toll-Like Receptor 7/metabolism , Toll-Like Receptor 8/metabolism , Transcription, Genetic , Tumor Necrosis Factor-alpha/genetics , 3' Untranslated Regions/genetics , Agammaglobulinaemia Tyrosine Kinase , Base Pairing/genetics , Cell Nucleus/metabolism , Cytokines/biosynthesis , Down-Regulation/genetics , Humans , Phosphorylation , Promoter Regions, Genetic/genetics , Toll-Like Receptor 4/metabolism , Transcription Factor RelA/metabolism , Tumor Necrosis Factor-alpha/metabolism
9.
Am J Hum Genet ; 101(3): 417-427, 2017 Sep 07.
Article in English | MEDLINE | ID: mdl-28886342

ABSTRACT

Individuals with Dupuytren disease (DD) are commonly seen by physicians and surgeons across multiple specialties. It is an increasingly common and disabling fibroproliferative disorder of the palmar fascia, which leads to flexion contractures of the digits, and is associated with other tissue-specific fibroses. DD affects between 5% and 25% of people of European descent and is the most common inherited disease of connective tissue. We undertook the largest GWAS to date in individuals with a surgically validated diagnosis of DD from the UK, with replication in British, Dutch, and German individuals. We validated association at all nine previously described signals and discovered 17 additional variants with p ≤ 5 × 10-8. As a proof of principle, we demonstrated correlation of the high-risk genotype at the statistically most strongly associated variant with decreased secretion of the soluble WNT-antagonist SFRP4, in surgical specimen-derived DD myofibroblasts. These results highlight important pathways involved in the pathogenesis of fibrosis, including WNT signaling, extracellular matrix modulation, and inflammation. In addition, many associated loci contain genes that were hitherto unrecognized as playing a role in fibrosis, opening up new avenues of research that may lead to novel treatments for DD and fibrosis more generally. DD represents an ideal human model disease for fibrosis research.


Subject(s)
Biomarkers/analysis , Dupuytren Contracture/genetics , Fibrosis/genetics , Genome-Wide Association Study/methods , Polymorphism, Single Nucleotide/genetics , Case-Control Studies , Cells, Cultured , Cohort Studies , Dupuytren Contracture/pathology , Fibrosis/pathology , Gene Expression Profiling , Genotype , Humans , Myofibroblasts/metabolism , Myofibroblasts/pathology , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Wnt Proteins/genetics , Wnt Proteins/metabolism
10.
Mol Clin Oncol ; 6(3): 384-388, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28451418

ABSTRACT

Acute myeloid leukemia (AML) is a clonal hematological malignant condition and the implications of pretreatment risk criteria as predictive or prognostic factors are constantly under evaluation. With this study, the authors' intent was to characterize AML patients and to evaluate the clinical outcome associated with Southwestern Oncology Group (SWOG) coding pretreatment risk criteria/cytogenetic score. Between 2002 and 2010, 225 patients were diagnosed with AML at the Portuguese Institute of Oncology (Porto, Portugal). From this patient group, 128 patients aged <65 years were selected. The patients were treated using a combination of cytarabine and anthracycline, with the addition of cyclosporine when bone marrow dysplasia was observed. A median survival of 24 months was observed in this group. The patients were divided in subgroups according to the SWOG pretreatment risk criteria. We observed a statistically significant association of non-favorable SWOG coding with female gender [P=0.025; risk ratio (RR)=3.632, 95% confidence interval (CI): 1.113-11.852], indication for allogeneic bone marrow transplantation (P=0.023, RR=1.317, 95% CI: 1.184-1.465), complete response achievement (P=0.013, RR=1.385, 95% CI: 11.232-1.556) and relapse (P=0.048, RR=3.181, 95% CI: 10.966-10.478). Furthermore, SWOG pretreatment risk criteria also significantly affected global overall survival (OS; P=0.003) and OS at 5 years (P=0.001). A multivariate Cox regression analysis supported response to induction therapy (3-year OS: P=0.011, RR=0.385, 95% CI: 10.184-0.806; 5-year OS: P=0.012, RR=0.388, 95% CI: 10.597-1.994), consolidation (3-year OS: P=0.005, RR=0.328, 95% CI: 0.150-0.720; 5-year OS: P=0.002, RR=0.308, 95% CI: 0.144-0.657) and the diagnosis of therapy-related aml (3-year OS: P=0.016, RR=2.756, 95% CI: 0.486-1.281; 5-year OS: P=0.031, RR=2.369, 95% CI: 1.081-5.189) as prognostic factors, but this was not confirmed for SWOG pretreatment risk criteria. Therefore, we concluded that the reproducibility of the application of the SWOG pretreatment risk criteria may not be available as a prognostic factor in every acute leukemia population. However, its application as a predictive factor of response has been confirmed in our population.

11.
Lasers Med Sci ; 32(5): 1041-1049, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28429193

ABSTRACT

Phototherapy using coherent light (lasers) and non-coherent light (light-emitting diodes (LEDs)) has been investigated for the purpose of biomodulation in biological tissues. Several effects can be expected, including pain moderation, biostimulation of cellular tropism, anti-inflammatory effects, regular circulatory stimulation, and tissue repair. The aim of this study was to evaluate the effect of LED (λ945 ± 20 nm, 48 mW) therapy on the regeneration process in femoral lesions of rats (Wistar). Seven irradiation sessions were held, with a 48-h interval between sessions. The animals were euthanised 14, 21, and 28 days after surgery. Bone samples were analysed by histomorphometry, micro X-ray fluorescence spectroscopy, scanning electron microscopy, and optical densitometry. The results demonstrated the effective positive influence of low-intensity LED therapy using the near-infrared region on the tissue repair process in diabetic animals, especially in the early stages of repair (14 and 21 days after surgery). It can be concluded that LED therapy positively influences bone formation in the early stages of the bone repair process in non-diabetic and diabetic animals, without causing changes in the optical density and volume of tissue in the final stages. No influence of LED therapy was observed on the percentage of calcium, percentage of phosphorus, Ca/P ratio, or optical mineral density in non-diabetic animals. However, increased mineral concentration was evident in the diabetic animals treated with the LED during the repair process.


Subject(s)
Diabetes Mellitus, Experimental/pathology , Femur/pathology , Femur/radiation effects , Infrared Rays , Phototherapy , Spectrometry, X-Ray Emission , Wound Healing/radiation effects , Animals , Densitometry , Femur/ultrastructure , Male , Rats, Wistar
12.
Oncol Lett ; 12(1): 262-268, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27347135

ABSTRACT

Therapy-related acute myeloid leukemia (t-AML) is a rare and almost always fatal late side effect of antineoplastic treatment involving chemotherapy, radiotherapy or the two combined. The present retrospective study intended to characterize t-AML patients that were diagnosed and treated in a single referral to an oncological institution in North Portugal. Over the past 10 years, 231 cases of AML were diagnosed and treated at the Portuguese Institute of Oncology of Porto, of which 38 t-AML cases were identified. Data regarding the patient demographics, primary diagnosis and treatment, age at onset of therapy-related myeloid neoplasm, latency time of the neoplasm, cytogenetic characteristics, AML therapy and outcome were collected from medical records. A previous diagnosis with solid tumors was present in 28 patients, and 10 patients possessed a history of hematological conditions, all a lymphoproliferative disorder. Breast cancer was the most frequent solid tumor identified (39.5% of all solid tumors diagnosed). The mean latency time was 3 years. In the present study, t-AML patients were older (P<0.001) and more frequently carried cytogenetic abnormalities (P=0.009) compared with de novo AML patients. The overall survival time was observed to be significantly poorer among individuals with t-AML (P<0.001). However, in younger patients (age, <50 years) there was no difference between the overall survival time of patients with t-AML and those with de novo AML (P=0.983). Additionally, patients with promyelocytic leukemia possess a good prognosis, even when AML occurs as a secondary event (P=0.98). To the best of our knowledge, the present study is the first to evaluate t-AML in Portugal and the results are consistent with the data published previously in other populations. The present study concludes that although t-AML demonstrates a poor prognosis, this is not observed among younger patients or promyelocytic leukemia patients.

13.
Photomed Laser Surg ; 33(7): 378-83, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26154726

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate surface roughness and changes in the composition of enamel submitted to different bleaching protocols and toothbrushing with regular and whitening toothpastes. BACKGROUND DATA: Bleaching treatment could promote morphological and chemical changes in enamel surface. METHODS: Enamel blocks were randomized into nine groups (n=10) according to the bleaching treatment (no bleaching, control group; 6% hydrogen peroxide, HP; or 10% carbamide peroxide, CP) and toothpaste used (placebo, PL; regular, R; or whitening dentifrice, W). Bleaching was performed according to manufacturers' instructions and all groups were submitted to 30,000 cycles of simulated toothbrushing with toothpaste (PL, R, or W). Mineral content evaluation and enamel roughness were evaluated initially (T1), after bleaching (T2), and after toothbrushing (T3), using an energy-dispersive micro X-ray fluorescence spectrometer and profilometry, respectively. Data were statistically analyzed with two way ANOVA, Tukey, and Dunnett tests (5%). RESULTS: Enamel surface roughness was influenced by bleaching and toothbrushing. Surface roughness increased for the groups that brushed with the placebo dentifrice (CP+PL, HP+PL, C+PL) and for the control group that brushed with whitening dentifrice (C+W). Enamel Ca/P ratio decreased after bleaching, but toothbrushing, regardless of the dentifrice used, did not reduce the enamel mineral content. CONCLUSIONS: The bleaching treatment resulted in a decrease of enamel mineral content, but the studied dentifrices did not contribute to surface mineral loss.


Subject(s)
Dental Enamel/drug effects , Dental Enamel/radiation effects , Dentifrices/pharmacology , Low-Level Light Therapy , Tooth Bleaching Agents/pharmacology , Tooth Bleaching , Humans , Surface Properties/drug effects , Surface Properties/radiation effects , Tissue Culture Techniques , Tooth Calcification/drug effects , Tooth Calcification/radiation effects , Toothbrushing
14.
EMBO Mol Med ; 7(5): 547-61, 2015 May.
Article in English | MEDLINE | ID: mdl-25770819

ABSTRACT

The mechanism by which trauma initiates healing remains unclear. Precise understanding of these events may define interventions for accelerating healing that could be translated to the clinical arena. We previously reported that addition of low-dose recombinant human TNF (rhTNF) at the fracture site augmented fracture repair in a murine tibial fracture model. Here, we show that local rhTNF treatment is only effective when administered within 24 h of injury, when neutrophils are the major inflammatory cell infiltrate. Systemic administration of anti-TNF impaired fracture healing. Addition of rhTNF enhanced neutrophil recruitment and promoted recruitment of monocytes through CCL2 production. Conversely, depletion of neutrophils or inhibition of the chemokine receptor CCR2 resulted in significantly impaired fracture healing. Fragility, or osteoporotic, fractures represent a major medical problem as they are associated with permanent disability and premature death. Using a murine model of fragility fractures, we found that local rhTNF treatment improved fracture healing during the early phase of repair. If translated clinically, this promotion of fracture healing would reduce the morbidity and mortality associated with delayed patient mobilization.


Subject(s)
Bone and Bones/drug effects , Bone and Bones/physiology , Fracture Healing/drug effects , Fractures, Bone/pathology , Immunity, Innate/drug effects , Tumor Necrosis Factor-alpha/administration & dosage , Tumor Necrosis Factor-alpha/metabolism , Animals , Bone and Bones/immunology , Chemokine CCL2/metabolism , Disease Models, Animal , Fracture Healing/immunology , Fractures, Bone/drug therapy , Humans , Mice , Monocytes/immunology , Neutrophils/immunology , Recombinant Proteins/administration & dosage , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Tumor Necrosis Factor-alpha/genetics
16.
J Biol Chem ; 289(26): 18347-59, 2014 Jun 27.
Article in English | MEDLINE | ID: mdl-24821726

ABSTRACT

The initial step of bone digestion is the adhesion of osteoclasts onto bone surfaces and the assembly of podosomal belts that segregate the bone-facing ruffled membrane from other membrane domains. During bone digestion, membrane components of the ruffled border also need to be recycled after macropinocytosis of digested bone materials. How osteoclast polarity and membrane recycling are coordinated remains unknown. Here, we show that the Cdc42-guanine nucleotide exchange factor FGD6 coordinates these events through its Src-dependent interaction with different actin-based protein networks. At the plasma membrane, FGD6 couples cell adhesion and actin dynamics by regulating podosome formation through the assembly of complexes comprising the Cdc42-interactor IQGAP1, the Rho GTPase-activating protein ARHGAP10, and the integrin interactors Talin-1/2 or Filamin A. On endosomes and transcytotic vesicles, FGD6 regulates retromer-dependent membrane recycling through its interaction with the actin nucleation-promoting factor WASH. These results provide a mechanism by which a single Cdc42-exchange factor controlling different actin-based processes coordinates cell adhesion, cell polarity, and membrane recycling during bone degradation.


Subject(s)
Endosomes/metabolism , Guanine Nucleotide Exchange Factors/metabolism , Intracellular Membranes/metabolism , Osteoclasts/cytology , Osteoclasts/metabolism , Animals , Bone and Bones/metabolism , Cell Adhesion , Cell Line , Cell Polarity , Guanine Nucleotide Exchange Factors/genetics , Mice , Protein Binding , cdc42 GTP-Binding Protein/metabolism
17.
Expert Opin Drug Metab Toxicol ; 9(12): 1625-34, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24053936

ABSTRACT

INTRODUCTION: Chemotherapy is the current standard treatment for hematological malignancies for both curative and palliative purposes. Unfortunately, in the current treatment scenario chemotherapy resistance is an issue that is know to lead to a relapse in cancer. The multidrug resistance 1 (MDR1) gene is often involved in drug resistance and, so far, the best studied mechanism of resistance relates to the level of P-glycoprotein (P-gp) expression on cancer cells; however, correlation with single nucleotide polymorphism (SNP) in the MDR1 gene has also been observed via a number of different mechanisms that interfere with function and expression of P-gp. AREAS COVERED: This article describes the influence of P-gp expression and SNP on the MDR1 gene in non-Hodgkin's lymphoma (NHL) and their effect on both its risk and outcome. The authors also provide a brief summary of the more important therapeutic options, which aim to overcome this drug resistance mechanism, and discuss their known mechanisms of action. EXPERT OPINION: There is evidence pertaining to an association between the outcome of NHL and P-gp expression. However, the authors emphasize the need for more studies to reinforce this evidence. Furthermore, there is a definite need for the therapeutic targets, which provide tumor cellular lines of interest, to be tested in humans, in order to better evaluate their toxicity and overall effect on the outcome. The ultimate aim of this research is to develop specifically designed therapies that are tailored to the intrinsic characteristics of specific patients.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Gene Expression Regulation, Neoplastic , Lymphoma, Non-Hodgkin/drug therapy , Lymphoma, Non-Hodgkin/genetics , Pharmacogenetics , ATP Binding Cassette Transporter, Subfamily B , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Drug Resistance, Neoplasm/genetics , Humans , Polymorphism, Single Nucleotide
18.
Int J Food Microbiol ; 154(3): 135-44, 2012 Mar 15.
Article in English | MEDLINE | ID: mdl-22264421

ABSTRACT

This study evaluated the effect of the supplementation of total dietary fiber from apple, banana or passion fruit processing by-products on the post-acidification, total titratable acidity, bacteria counts and fatty acid profiles in skim milk yoghurts co-fermented by four different probiotics strains: Lactobacillus acidophilus L10 and Bifidobacterium animalis subsp. lactis BL04, HN019 and B94. Apple and banana fibers increased the probiotic viability during shelf-life. All the fibers were able to increase the short chain and polyunsaturated fatty acid contents of yoghurts compared to their respective controls. A synergistic effect between the type of fiber and the probiotic strain on the conjugated linoleic acid content was observed, and the amount of α-linolenic acid was increased by banana fiber. The results of this study demonstrate, for the first time, that fruit fibers can improve the fatty acid profile of probiotic yoghurts and point out the suitability of using fibers from fruit processing the by-products to develop new high value-added fermented dairy products.


Subject(s)
Dietary Fiber/pharmacology , Fruit , Probiotics/pharmacology , Yogurt/microbiology , Bifidobacterium/metabolism , Dairy Products/microbiology , Fatty Acids/analysis , Fermentation , Lactobacillus acidophilus/metabolism , Linoleic Acids, Conjugated/analysis , Linoleic Acids, Conjugated/biosynthesis , Probiotics/analysis , Yogurt/analysis
19.
Microsc Res Tech ; 75(6): 703-10, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22131274

ABSTRACT

PURPOSE: This work aims to study the erosion on restorative materials and on surrounding dentin. Fifty root dentin samples were obtained from bovine incisors. METHODS: Twenty samples were not restored and thirty received cavity preparations. Samples were assigned to five groups: G1, G2: sound dentin (D); G3: composite resin (CR); G4: resin-modified glass-ionomer cement (RMGIC); G5: glass-ionomer cement (GIC). The samples of groups 2-5 were submitted to six cycles (demineralization-remineralization). Samples were analyzed by micro energy-dispersive X-ray fluorescence spectrometry (µ-EDXRF) and by scanning electron microscopy (SEM). RESULTS: Mineral loss was greater in G2 samples than in RMGI > CR > GIC > D (control). SEM images showed pronounced dentin demineralization in groups 2 and 4. The acid erosion has a significant effect on mineral loss (Ca and P) of root dentin without restoration. CONCLUSIONS: Composite resin had the best chemical resistance to erosion among all the materials. Fluoride contained in GIC seemed to cause some protection, however, with material degradation. Chemical interaction of tooth-colored dental materials with root dentin could be assessed by µ-EDXRF.


Subject(s)
Dental Materials/chemistry , Dentin/chemistry , Incisor/anatomy & histology , Incisor/chemistry , Tooth Erosion , Animals , Cattle , Microscopy, Electron, Scanning , Minerals/analysis , Spectrometry, X-Ray Emission
20.
Microsc Res Tech ; 74(9): 839-44, 2011 Sep.
Article in English | MEDLINE | ID: mdl-23939672

ABSTRACT

BACKGROUND: Dental erosion is a risk factor for dental health, introduced by today's lifestyle. Topical fluoride applications in the form of varnishes and gel may lead to deposition of fluoride on enamel. PURPOSE: This in vitro study aimed to evaluate the effect of two fluoride varnishes and one fluoride gel on the dissolution of bovine enamel by acids. METHODS: Enamel samples (72) were divided (n = 8): artificial saliva (control-G1), Pepsi Twist® (G2), orange juice (G3), Duraphat® + Pepsi Twist® (G4), Duraphat® + orange juice (G5), Duofluorid® + Pepsi Twist® (G6), Duofluorid® + orange juice (G7), fluoride gel + Pepsi Twist® (G8), and fluoride gel + orange juice (G9). Fluoride gel was applied for 4 min and the varnishes were applied and removed after 6 h. The samples were submitted to six cycles (demineralization: Pepsi Twist® or orange juice, 10 min; remineralization: saliva, 1 h). Samples were analyzed by energy-dispersive X-ray fluorescence (144 line-scanning). RESULTS: The amount of Ca and P decreased significantly in the samples of G2 and G3, and the Ca/P ratio decreased in G3. Mineral gain (Ca) was greater in G9 samples than in G4 > G3 > G5 > G1, and (P) greater in G7 samples than in G9 > G4-6 > G2-3. CONCLUSIONS: The protective effect of Duofluorid® was significantly lower than fluoride gel against orange juice. The fluoride varnishes can interfere positively with the dissolution of dental enamel in the presence of acidic beverages. Fluoride gel showed the best protection level to extrinsic erosion with low costs.


Subject(s)
Acids/toxicity , Dental Enamel/drug effects , Fluorides, Topical/administration & dosage , Gels/administration & dosage , Surface Properties , Tooth Erosion/prevention & control , Animals , Cattle , Dental Enamel/ultrastructure , In Vitro Techniques , Spectrometry, X-Ray Emission
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